The present invention relates to a liquid crystal module of a direct below installed light type that is incorporated in a liquid crystal television or a personal computer, and more particularly to a liquid crystal module that can reduce the influence of heat generation from an end part having a pin terminal of a cold cathode tube by improving a fixing structure of a lamp frame for a lamp socket.
As the liquid crystal module of the direct below installed light type that is incorporated in a large liquid crystal television, a liquid crystal module is known in which a plurality of sets of straight cold cathode tubes, the one set of which includes the two cold cathode tubes, are arranged in a rear frame, lamp sockets are provided in both sides of the two cold cathode tubes of each set, and pin terminals at one ends of the cold cathode tubes of each set are connected together by a connecting plate to obtain a U shaped cold cathode tube. In such a liquid crystal module, as shown in FIG. 5, the end parts of the two cold cathode tubes 3 and 3 as one set having the pin terminals are inserted into hollow holding parts 4a and 4a at both end parts of the lamp socket 4 from slit parts 4b and 4b and held, and protrusions 4d and 4d in a lower face of the lamp socket 4 are inserted into holes formed on a bottom plate 1a of a rear frame 1 to attach the lamp socket 4 along a side plate of the rear frame 1. Then, a lamp frame 5 for covering the lamp socket 4 is installed inside the side plate of the rear frame 1 to press and fix an upper face of the lamp socket 4 by a socket pressing part 5d formed in a rear plate part 5c of the lamp frame 5.
On the other hand, as a related art concerning the attachment of the lamp socket of the liquid crystal module, for instance, a technique is known in which a lamp socket is soldered and fixed to a balance PCB in a supporter corresponding to the above-described lamp frame (Patent Document 1). As another related art, a technique is known in which a lamp socket is detachably connected to a connector on the face of a base board in a sub-frame corresponding to the above-described lamp frame (Patent Document 2).    [Patent Document 1] Japanese Patent Publication Number 2008-146050    [Patent Document 2] Japanese Patent Publication Number 2007-080627
However, as in the related liquid crystal module shown in FIG. 5, when the upper face of the lamp socket 4 is pressed and fixed by the socket pressing part 5d formed in the rear plate part 5c of the lamp frame 5, since both end parts of the lamp socket 4 in which the hollow holding parts 4a and the slit parts 4b are provided are heated by heat generated from both the ends of the cold cathode tubes 3 and 3 having the pin terminals so that the socket pressing part 5d of the lamp frame 5, especially, the temperature of parts pressing both the end parts of the lamp socket 4 is high, a countermeasure is taken that the lamp frame 5 molded by a synthetic resin having high heat resisting temperature is used or a current value of the cold cathode tube 3 is lowered to be used. However, a problem arises that the lamp frame made of the heat resisting synthetic resin causes a cost to be increased. Further, when the current value of the cold cathode tube is lowered to be used, since the number of the cold cathode tubes 3 needs to be increased so as not to lower a luminance, a problem also arises that the cost is increased.
On the other hand, since the techniques for fixing the lamp socket disclosed in the Patent Documents 1 and 1 are essentially different from the technique for fixing the lamp socket of the related liquid crystal module shown in FIG. 5. Accordingly, it is impossible that the techniques of the Patent Documents 1 and 2 may be applied to the related liquid crystal module as means for solving the above-described problems.